In the electrolytic refining of a metal M, what would you take as the anode, the cathode, and the electrolyte?

A rod of impure metal M would be used as an anode and a thin strip of pure metal M would be used as the cathode. A water-soluble salt of metal M would be used as an electrolyte. When current is passed through the electrolyte, the impure metal from the anode is dissolved in the electrolyte and an equal amount of pure metal from the electrolyte is deposited on the cathode.